QP
0.7SNAPSHOT
Control software for the ??SRT telescope

Encapsulates a few time properties which are astronomically relevant. More...
#include <astrotime.h>
Public Member Functions  
const double  gmst_2pi (void) const 
The following calculates GMST of date, in radians. More...  
const double  lmst (void) const 
Returns the Local Mean Sidereal Time at the observatory.  
const double  ut1 (void) const 
Return UT1 as a number of hours. More...  
const int  mjd (void) const 
Return the MJD at time 00:00 on the indicated day. More...  
AstroTime ()  
The default constructor produces a valid, but largely useless structure, representing midnight on 1858 November 17 (MJD=0) at the meridian.  
AstroTime (const int year, const int month, const int day, const int hour, const int minute, const double second, const double obslong)  
Create a new time. More...  
AstroTime (const AstroTime &ref, const double extra_secs)  
Return a new astrotime, with the time given by the tm struct. More...  
AstroTime (const int year, const int month, const int day)  
Create a new time. More...  
AstroTime  move (double obs_lon) 
Return a new AstroTime representing the same UT as this one, but for a different observatory longitude. More...  
char *  str (char *, size_t) 
Format the current time into the given buffer. More...  
Encapsulates a few time properties which are astronomically relevant.
AstroTime::AstroTime  (  const int  year, 
const int  month,  
const int  day,  
const int  hour,  
const int  minute,  
const double  second,  
const double  obslong  
) 
Create a new time.
The time must be given in UT1.
year  must be after 1859 (ie, positive MJD) 
month  month in [1, 12] 
day  day in [1, 31] 
hour  UT1 hour, positive 
minute  UT1 minute, positive 
second  UT1 second, positive 
obslong  the observatory eastlongitude, in radians 
AstroTime::AstroTime  (  const AstroTime &  ref, 
const double  extra_secs  
) 
Return a new astrotime, with the time given by the tm struct.
Returns a new time, offset from the reference time by a number of UT1 seconds.
AstroTime::AstroTime  (  const int  year, 
const int  month,  
const int  day  
) 
Create a new time.
The time is given in LST on the supplied date. LST must be supplied in radians in the range [0,2pi). Create a new time, defaulting to noon.
const double AstroTime::gmst_2pi  (  void  )  const 
The following calculates GMST of date, in radians.
This evaluates the expression for GMST in terms of UT, as given in Explanatory Supplement Eq.2.241, but with the resulting time normalised to be in [0,2pi)
const int AstroTime::mjd  (  void  )  const 
Return the MJD at time 00:00 on the indicated day.
This is a round number.
AstroTime AstroTime::move  (  double  new_obs_lon  ) 
Return a new AstroTime representing the same UT as this one, but for a different observatory longitude.
new_obs_lon  the observatory eastlongitude, in radians 
char * AstroTime::str  (  char *  buf, 
size_t  buflen  
) 
Format the current time into the given buffer.
buf  a buffer to receive the formatted string 
buflen  the size of this buffer; if the string would be longer than this it is truncated 
const double AstroTime::ut1  (  void  )  const 
Return UT1 as a number of hours.
The result is always in the range [0, 24).